ミトコンドリアのカルシウムユニポーターは,非常に選択的なイオンチャネルである
Yuriy Kirichok1, Grigory Krapivinsky, David E Clapham
1Howard Hughes Medical Institute, Department of Cardiovascular Research, Children's Hospital, andHarvard Medical School, 320 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|January 23, 2004
まとめ
ミトコンドリアはミトコンドリアカルシウムユニポーター (MCU) を通してカルシウムを吸収します. 研究者らは,ミトコンドリア内膜に新しい,高アフィニティのCa2+選択イオンチャネルを発見し,それをMCUとして特定しました.
科学分野:
- 細胞生物学 細胞生物学
- ミトコンドリア生理学 ミトコンドリア生理学
- 交通機関 交通機関 交通機関
背景:
- ミトコンドリアはシグナル伝達中に細胞溶液Ca2+を蓄積する.
- ミトコンドリアのCa2+吸収は,エネルギー生産,Ca2+シグナルダイナミクス,細胞死に影響を与えます.
- ミトコンドリアのカルシウムユニポーター (MCU) によって媒介されるミトコンドリアのCa2+吸収のメカニズムは,以前,チャネルまたはキャリアとして議論されていました.
研究 の 目的:
- ミトコンドリアカルシウムユニポーター (MCU) の分子同一性と性質を決定する.
- MCUがイオンチャネルまたはキャリアとして機能するかどうかを調査する.
主な方法:
- 内 mitochondrial 膜のパッチ-クランプ.
- 新しいイオンチャネルを通るCa2+フクロスの特徴.
- Ca2+に対するチャネル親和性と選択性の評価.
- 既知のMCU阻害剤に関連してチャネル特性の評価.
主要な成果:
- ミトコンドリア内膜にCa2+選択イオンチャネルが発見されました.
- このチャネルはCa2+ (Kd ≤ 2 nM) に対して非常に高い親和性を示す.
- このチャネルは内側を修正し,Ca2+を活性化されたミトコンドリアに吸収することを促進しています.
- チャンネル特性は,MCUで期待されるものと一致し,MCU阻害剤に敏感です.
結論:
- ミトコンドリアカルシウムユニポーター (MCU) は,Ca2+選択イオンチャネルである.
- このチャネルの高い親和感と内側修正により,効率的なミトコンドリアCa2+吸収が可能になります.
- この発見は,MCUの性質に関する長年にわたる議論を明確にします.
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